From npark@kth.se Thu Apr 07 09:24:24 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!kth!npark
From: npark@kth.se (Nadine Park)
Newsgroups: comp.dsp
Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Apr07.092424.8014@kth.se>
Date: Thu, 07 Apr 1994 09:24:24 GMT
Organization: Royal Institute of Technology, Stockholm
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Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.

A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.
At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs.

Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble.

-- 
=== Nadine Park ===
Dept of Electrical Engineering, Royal Institute of Technology, Stockholm
"A soul is not exclusive to biology."

From jnovak@earthlink.net Sat Apr 09 10:49:24 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!earthlink!jnovak
From: jnovak@earthlink.net (Ji-woo Novak)
Newsgroups: comp.dsp
Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Apr09.104924.8620@earthlink.net>
Date: Sat, 09 Apr 1994 10:49:24 GMT
References: <1994Apr07.092424.8014@kth.se>
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In article <1994Apr07.092424.8014@kth.se>, npark@kth.se (Nadine Park) writes:
> Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.

I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection.

-- 
Ji-woo Novak
Tape trading list upon request. SASE required for international mail.

From tpopov@u-tokyo.ac.jp Mon Apr 11 04:00:24 1994
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!tpopov
From: tpopov@u-tokyo.ac.jp (Tomas Popov)
Newsgroups: comp.dsp
Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Apr11.040024.8953@u-tokyo.ac.jp>
Date: Mon, 11 Apr 1994 04:00:24 GMT
References: <1994Apr07.092424.8014@kth.se>
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In article <1994Apr07.092424.8014@kth.se>, npark@kth.se (Nadine Park) writes:
> Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.
> A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.

I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection.

Top-posters will be placed in my ~/.killfile without notice.

-- 
Tomas Popov | tpopov@u-tokyo.ac.jp
PGP Key fingerprint: FB21 1EB8 BD0F F222
"Keep the channels open."